''Zupaysaurus'' (; "ZOO-pay-SAWR-us") is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of early

theropod Theropoda (; ), whose members are known as theropods, is a dinosaur clade that is characterized by hollow bones and three toes and claws on each limb. Theropods are generally classed as a group of saurischian dinosaurs. They were ancestrally c ...

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

living during the Norian stage of the

Late Triassic The Late Triassic is the third and final epoch of the Triassic Period in the geologic time scale, spanning the time between Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch. ...

in what is now

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

. Fossils of the dinosaur were found in the

Los Colorados Formation The Los Colorados Formation is a sedimentary rock formation of the Ischigualasto-Villa Unión Basin, found in the provinces of San Juan and La Rioja in Argentina. The formation dates back to the Norian age of the Late Triassic. The up to thick f ...

of the Ischigualasto-Villa Unión Basin in northwestern Argentina. Although a full skeleton has not yet been discovered, ''Zupaysaurus'' can be considered a

biped Bipedalism is a form of terrestrial locomotion where an organism moves by means of its two rear limbs or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning 'two feet' (from Latin ''bis'' 'double' ...

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

, up to long. It may have had two parallel crests running the length of its snout.

Discovery

Discovered in May 1997 by Santiago Reuil ("Vultur"), part of the crew of Guillermo Rougier, it was later described by Arcucci and Coria and published in 2003. The name ''Zupaysaurus'' is composed of the

Quechua Quechua may refer to: *Quechua people, several indigenous ethnic groups in South America, especially in Peru *Quechuan languages, a Native South American language family spoken primarily in the Andes, derived from a common ancestral language **So ...

word ''supay'' meaning "devil" and the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

word ' () meaning "lizard"; thus "devil lizard". In Incan mythology, ''

supay In the Quechua, Aymara, and Inca mythologies, Supay was both the god of death and ruler of the '' Ukhu Pacha'', the Incan underworld, as well as a race of demons. Supay is associated with miners' rituals. With the Spanish colonization of the Amer ...

'' was both the god of death and ruler of the '' ukhu pacha'', the Incan underworld. The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

was named ''Z. rougieri'' in the honor of Guillermo Rougier, the scientist who led the expedition which discovered and collected the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of sever ...

(original specimen) PULR-076. ''Zupaysaurus'' was first described and named in the scientific journal ''

Ameghiniana ''Ameghiniana'' is a peer-reviewed scientific journal covering palaeontology published by the Asociación Paleontológica Argentina. It is named after the 19th century Italian Argentine palaeontologist Florentino Ameghino. The discovery of many ...

'' by Argentine

paleontologist Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...

s Andrea Arcucci and

Rodolfo Coria Rodolfo Aníbal Coria (born in Neuquén June 1, 1959), is an Argentine paleontologist. He is best known for having directed the field study and co-naming of '' Argentinosaurus'' (possibly the world's largest land animal ever) in 1993, and ''Giga ...

in 2003.

Description

''Zupaysaurus'' was a medium-sized theropod. An adult

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, th ...

, measured approximately in length, suggesting a body length of approximately from its snout to the tip of its tail. In 2010

Gregory S. Paul Gregory Scott Paul (born December 24, 1954) is an American freelance researcher, author and illustrator who works in paleontology, and more recently has examined sociology and theology. He is best known for his work and research on theropod dino ...

gave a length of 6 meters (20 ft) and a weight of 250 kg (550 lbs). In 2016 it was given a much smaller size of 4.2 meters (14 ft) and 70 kg (154 lbs). Like all theropods, ''Zupaysaurus'' walked only on its hindlegs, leaving its forelimbs free to grasp its

prey Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill ...

. The length of the neck bones recovered suggests that this genus has a rather long neck. Like the

coelophysoids Coelophysoidea were common dinosaurs of the Late Triassic and Early Jurassic periods. They were widespread geographically, probably living on all continents. Coelophysoids were all slender, carnivorous forms with a superficial similarity to the ...

, ''Zupaysaurus'' has a kink in its snout, between the

premaxilla The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammal has ...

ry and

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. T ...

ry bones of the upper jaw. It is estimated that ''Zupaysaurus'' had 24 teeth and an intermandibular hinge is present in the lower jaw.Arcucci, A.B. & Coria R.A. 2003. A new Triassic carnivorous dinosaur from Argentina. ''

'' 40(2):217-228. Only one specimen of ''Zupaysaurus'' is known to science. The

specimen was designated PULR-076, which consists of a nearly complete skull which was very well preserved, the right

shoulder The human shoulder is made up of three bones: the clavicle (collarbone), the scapula (shoulder blade), and the humerus (upper arm bone) as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder mak ...

girdle, the lower right leg and

ankle The ankle, or the talocrural region, or the jumping bone (informal) is the area where the foot and the leg meet. The ankle includes three joints: the ankle joint proper or talocrural joint, the subtalar joint, and the inferior tibiofibular joi ...

, and twelve

vertebra The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristi ...

e from the neck, back, and hips. Additional material of a smaller individual found at the same site may or may not belong to ''Zupaysaurus''. As ''Zupaysaurus'' was originally described, the head bore two thin parallel crests on top of the skull, similar to theropods like ''

Dilophosaurus ''Dilophosaurus'' ( ) is a genus of theropod dinosaurs that lived in what is now North America during the Early Jurassic, about 193 million years ago. Three skeletons were discovered in northern Arizona in 1940, and the two best preserve ...

'' and '' Coelophysis kayentakatae''. These crests are thought to have been formed by the nasal bones solely, unlike those of many other theropods which also incorporated the lacrimal bones. Crests on the skull were pervasive among theropods and may have been used for communicative purposes such as species or gender recognition.Currie, P.J. & Zhao X. 1993. A new carnosaur (Dinosauria, Theropoda) from the Jurassic of Xinjiang, People's Republic of China. ''Canadian Journal of Earth Sciences'' 30: 2037-2081. However, more recent analysis of the skull has cast doubt on the presence of these crests in ''Zupaysaurus''. An unpublished abstract presented at a recent conference indicated the structures initially identified as crests were in fact the lacrimal bones displaced upwards during the process of

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

ization.Ezcurra, M.D. & Novas, F.E. 2005. Phylogenetic relationships of the Triassic theropod ''Zupaysaurus rougieri'' from NW Argentina. Presented in August 2005 during th
II Latin American Congress of Vertebrate Paleontology
in

Rio de Janeiro Rio de Janeiro ( , , ; literally 'River of January'), or simply Rio, is the capital of the state of the same name, Brazil's third-most populous state, and the second-most populous city in Brazil, after São Paulo. Listed by the GaWC as a ...

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

. This analysis will be published in peer-reviewed print form later in 2006. A summary of the talk can be see
here
Other cranial ornamentation included a rugose laterally-projecting lacrimal ridge on the top of the skull.

A diagnosis is a statement of the anatomical features of an organism (or group) that collectively distinguish it from all other organisms. Some, but not all, of the features in a diagnosis are also autapomorphies. An autapomorphy is a distinctive anatomical feature that is unique to a given organism or group. According to Ezcurra (2006) and Ezcurra and Novas (2006), ''Zupaysaurus'' can be distinguished based on the following characteristics: the maxillary fenestra is within the antorbital fossa (according to Ezcurra, 2006), the rostral process of the lacrimal is ventrally bowed (according to Ezcurra, 2006), the ventral process of the

squamosal The squamosal is a skull bone found in most reptiles, amphibians, and birds. In fishes, it is also called the pterotic bone. In most tetrapods, the squamosal and quadratojugal bones form the cheek series of the skull. The bone forms an ancestral co ...

is kinked (according to Ezcurra, 2006), wide contact between squamosal and

quadratojugal The quadratojugal is a skull bone present in many vertebrates, including some living reptiles and amphibians. Anatomy and function In animals with a quadratojugal bone, it is typically found connected to the jugal (cheek) bone from the front and ...

(according to Ezcurra, 2006). The maxillary-jugal ventral margin describes an obtuse angle in lateral view (according to Ezcurra and Novas, 2006), a notch on the dorsal margin of the ascending process of the maxilla, relating to horizontal ramus of the lacrimal is rostrally tapering onto the forked caudal tip of the ascending process of the

; (according to Ezcurra and Novas, 2006), a lacrimal with a highly pneumatized antorbital recess (according to Ezcurra and Novas, 2006), a short and square-shaped retroarticular process of the

mandible In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone ...

(according to Ezcurra and Novas, 2006), the

cnemial crest The cnemial crest is a crestlike prominence located at the front side of the head of the tibiotarsus or tibia in the legs of many mammals and reptiles (including birds and other dinosaurs). The main extensor muscle of the thigh In human anat ...

is poorly developed (according to Ezcurra and Novas, 2006).

Classification

''Zupaysaurus'' was classified as the earliest known

tetanuran Tetanurae (/ˌtɛtəˈnjuːriː/ or "stiff tails") is a clade that includes most theropod dinosaurs, including megalosauroids, allosauroids, tyrannosauroids, ornithomimosaurs, compsognathids and maniraptorans (including birds). Tetanurans ar ...

theropod due to several features of its skull, dentition, and hindlimb. However, several features typical of more basal theropods were also noted by the original authors. Analyses by Carano (2005), Tykoski (2005), and Ezcurra and Novas (2005) have classified ''Zupaysaurus'' as a

coelophysoid Coelophysoidea were common dinosaurs of the Late Triassic and Early Jurassic periods. They were widespread geographically, probably living on all continents. Coelophysoids were all slender, carnivorous forms with a superficial similarity to the ...

related to '' Segisaurus'' and probably '' Liliensternus'', though more basal than ''

Coelophysis ''Coelophysis'' ( traditionally; or , as heard more commonly in recent decades) is an extinct genus of coelophysid theropod dinosaur that lived approximately 228 to 201.3 million years ago during the latter part of the Triassic Period fro ...

''.Carrano, M.T., Hutchinson, J.R., & Sampson, S.D. 2005. New information on ''Segisaurus halli'', a small theropod dinosaur from the Early Jurassic of Arizona. ''Journal of Vertebrate Paleontology'' 25(4): 835-849. Yates (2006) found ''Zupaysaurus'' to form a group with ''Dilophosaurus'' and ''

Dracovenator ''Dracovenator'' () is a genus of neotheropod dinosaur that lived approximately 201 to 199 million years ago during the early part of the Jurassic Period in what is now South Africa. ''Dracovenator'' was a medium-sized, moderately-built, ground ...

'', placing it in a monophyletic Dilophosauridae.Yates, A.M., 2006 (for 2005). "A new theropod dinosaur from the Early Jurassic of South Africa and its implications for the early evolution of theropods." ''Palaeontologia Africana'', 41: 105-122. But later studies found ''Zupaysaurus'' to be a sister taxon sister to a clade containing dilophosaurids,

ceratosaurs Ceratosaurs are members of the clade Ceratosauria, a group of dinosaurs defined as all theropods sharing a more recent common ancestor with ''Ceratosaurus'' than with birds. The oldest known ceratosaur, ''Saltriovenator'', dates to the earliest ...

and

tetanurans Tetanurae (/ˌtɛtəˈnjuːriː/ or "stiff tails") is a clade that includes most theropod dinosaurs, including megalosauroids, allosauroids, tyrannosauroids, ornithomimosaurs, compsognathids and maniraptorans (including birds). Tetanurans ar ...

.Nesbitt, S. J., Smith, N. D., Irmis, R. B., Turner, A. H., Downs, A., & M. A. Norell. 2009. A complete skeleton of a Late Triassic saurischian and the early evolution of dinosaurs. Science 326:1530-1533. Below is a

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ...

based on the phylogenetic analysis conducted by Sues et al. in 2011, showing the relationships of ''Zupaysaurus'':Hans-Dieter Sues, Sterling J. Nesbitt, David S. Berman and Amy C. Henrici (2011). "A late-surviving basal theropod dinosaur from the latest Triassic of North America". Proceedings of the Royal Society B 278 (1723): 3459–3464

Paleoecology

''Zupaysaurus'' was discovered in red siliciclastic sediments at the "Quebrada de los Jachaleros" locality within the

of the

La Rioja La Rioja () is an autonomous community and province in Spain, in the north of the Iberian Peninsula. Its capital is Logroño. Other cities and towns in the province include Calahorra, Arnedo, Alfaro, Haro, Santo Domingo de la Calzada, an ...

province in Argentina. This

formation Formation may refer to: Linguistics * Back-formation, the process of creating a new lexeme by removing or affixes * Word formation, the creation of a new word by adding affixes Mathematics and science * Cave formation or speleothem, a secondar ...

has been shown by magnetostratigraphy to date to the Norian stage of the

period, approximately 228 to 208 million years ago.Weishampel, D.B., Barrett, P.M., Coria, R.A., Le Loueff, J., Xu X., Zhao X., Sahni, A., Gomani, E.M.P., & Noto, C.R. 2004. Dinosaur distribution. In: Weishampel, D.B., Dodson, P., & Osmólska, H. (Eds.). ''The Dinosauria'' (2nd Edition). Berkeley: University of California Press. Pp. 517-606. but has also been assigned to the slightly younger Rhaetian stage, which was approximately 208 to 201 million years ago.Heckert, A.B. & Lucas, S.G. 1998. Global correlation of the Triassic theropod record. ''Gaia'' 15: 63-74. ot printed until 2000/ref> Both specimens assigned to this genus are housed in the collection of the National University of La Rioja in

La Rioja, Argentina La Rioja () is the capital and largest city of La Rioja Province, Argentina, located in the east of the province. La Rioja is located on the foot of the Velasco Sierras, from Buenos Aires, and from Córdoba. History It was founded in 159 ...

. The

was interpreted as an ancient floodplain and it was home to several types of early

sauropodomorph Sauropodomorpha ( ; from Greek, meaning "lizard-footed forms") is an extinct clade of long-necked, herbivorous, saurischian dinosaurs that includes the sauropods and their ancestral relatives. Sauropods generally grew to very large sizes, had lon ...

dinosaurs (including '' Riojasaurus'', '' Coloradisaurus'' , and ''

Lessemsaurus ''Lessemsaurus'' is an extinct genus of sauropod dinosaur belonging to Lessemsauridae. Naming and description The type species, ''L. sauropoides'', was formally described by José Fernando Bonaparte in 1999 in honor of Don Lessem, a writer of ...

''), all of which shared the same paleoenvironment with ''Zupaysaurus''. It is recognized as one of the earliest known faunal assemblages dominated by dinosaurs, which were 43% of the number of tetrapod species currently known. The non-dinosaurs that inhabited this locality included

pseudosuchians Pseudosuchia is one of two major divisions of Archosauria, including living crocodilians and all archosaurs more closely related to crocodilians than to birds. Pseudosuchians are also informally known as "crocodilian-line archosaurs". Prior to ...

therapsids Therapsida is a major group of eupelycosaurian synapsids that includes mammals, their ancestors and relatives. Many of the traits today seen as unique to mammals had their origin within early therapsids, including limbs that were oriented mo ...

like Cynodontia, other early reptiles, and possible

archosaurs Archosauria () is a clade of diapsids, with birds and crocodilians as the only living representatives. Archosaurs are broadly classified as reptiles, in the cladistic sense of the term which includes birds. Extinct archosaurs include non-avia ...

References

External links

*
Zupaysaurus
' entry in The Theropod Database. {{Portal bar, Dinosaurs Prehistoric neotheropods Dinosaur genera Norian life Late Triassic dinosaurs of South America Triassic Argentina Fossils of Argentina Los Colorados Formation Fossil taxa described in 2003 Taxa named by Rodolfo Coria